Method and apparatus for making tires



m. SCHRANK. METHOD AND APPARATUS FOR MAKING TIRES. APPLICATION FILED FEB. I8, I921. RENEWED SEPT I5, I921.

Patented Apr. 4; I922 2 SHEETS-SHEET I- F. 1. SCHBANK. METHOD AND APPARATUS FOR MAKING T IRES. APPLICATION FILED FEB, I8, 1921- RENEWED SEPT. 15. 1921-' 1 4M 1 7% Patented A r. 4 1922.

v 2 SHEETS-SHEET 2. :M

I UNITED STATES PATENT OFFIC FRED J. SCHRANK, OF AKRON, OHIO, ASSIGNOR TO THE SWINEHART TIRE & RUBBER COMPANY, OF AKRON, OHIO, A CORPORATION OF OHIO.

METHOD AND APPARATUS FOR MAKING TIRES.

Specification of Letters Patent.

Patented Apr. 4, g 1922.

Original application filed December 31, 1920, Serial No. 434,230. Divided and this' application filed February 18, 1921, Serial No. 446,084. Renewed September 15, 1921. Serial No. 500,967.

T all whom it may concern.

Be it known that I, FRED J. SOHRANK, a

' citizen of the United States, residin .at

Akron, in the county of Summit and tate of Ohio, have invented new and useful Improvements in the Method and Apparatus for Making Tires, of which the following is -a specification, reference being bad to the accompanying drawing.

This invention relates to vehicle tires and especially to those of the cushion type as employed particularly on self-propelled trucks, although not restricted thereto. Such tires are made of some elastic cushion ing material, as exemplified by a rubber composition, and my invention has for its objects the provision of a structure which shall possess an enhanced cushioning'eifect, which shall stand extreme overloads and other hard usage with a minimum of injury, and as a result shall afford unusually long wear. Other objects of the invention are the provision of a cellular tire having means for impeding the entrance of sand and foreign matter into the cells and for decreasing the weakening effect of those cells; the provision of new and improved apparatus and methods for producingsuch a tire; while further objects and advantages of the invention will appear as the description proceeds.

In the drawings accompanying and forming a part of this application, I have shown certain illustrative embodiments of my invention although without intent to limit myself thereto, since the same can be embodied in numerous other specific forms. Fig. 1 represents a cross sectional view and Fig. 2

a partial elevation of a tire embodyingmy improvements; Figs. 3 and 4 are similar views of a modified construction; Figs. 5 and 6 are similar views of another modified construction; Fig. 7 is across sectional view of the mold and associated parts preferably employed in making my improved tire; and Fig. 8 is a sectional view on the line 8-8 of Fig. 7.

Broadly speaking, my invention consists in molding in the tread portions of a solid elastic tire, a plurality of openings extending small or large, deep or shallow.

Ilescribing by reference characters the parts shown in the drawings, 1 represents the flanged rim or tire base, and 2 represents the elastic cushioning material mounted thereon and constituting the tire. Neither the shape of the rim nor the shape, design or mode of attachment of the tire is important to the present invention. 3-3 represent annular recesses which extend from the tread portion of the tire into the substance there.- of the desired distance, and 4-4 represent the. cores located therein. In Figs. 1 and 2 the cores are integral with the tire substance and slightly shorter than the recesses so as to terminate a short distance inside the tread. The recesses are also arranged at an angle to the radius but parallel to the plane of the wheel. In Figs. 3' and 4 the cores are also integral with the tire substance, and inclined to the radius, but are also inclined to the plane of thewheel and project flush with the surface of the tread. In Figs. 5 and 6 the cores are made of a separate flexible substance, adhesively united at their inner ends to the tire material and arranged parallel to the radii and to the plane of the wheel. The above named variations and arrangements and substances can be varied indefinitely, as can also the relative sizes of core and opening, although in most cases a small clearance is left between the core and opening in order to afford traction and to afford an alternate inspiration and expiration of air during the revolution of the tire so that of therecesses as they approach the ground or working portions of the tire, thereby minimizing the entrance of dirt. cesses also have a tendency to decrease slipping and skidding, particularly in case the cores be somewhat shorter than the holes, and in practice these cores tend to wear away slightly faster than the tread itself, thereby maintaining this condition, although by making them of the proper substance this can be overcome.

The preferred process and apparatus for producin this tire is shown in Figs. 7 and 8, in which 10 and-11 represent the upper and lower mating halves of a tire'mold whose adjacent faces are formed with the grooves 12-12 for the rim or tire base, and also preferably for the base rings 13, and with inclined portions 14:14: for the sides of the tire. Around. the tread portion of the tire there are located the interfitting pinpositioning rings 15 formed with suitable apertures 16 for the reception of the cell pins 1717 which are driven into the tire material in any suitable manner after the. various parts have been positioned in the mold as above described but prior to the placing of pressure thereon. The inner end of each pin is hollow as shown at 18, such cavity extending as far out as it is desired that the core should project and being vented by the ducts 19. After the pins have been forced into. place they are SUIIOIIIKl'Gd by the retaining ring 20 which is clamped tightly in any suitable manner as by the clamp screw 21. Pressure isthen applied to the mold in thedirection indicated by the arrow (c-(t in any suitable manner such as a hydraulic press, whereby the cushioning material is forced thoroughly into the pins and into contact with all parts of the mold space, and the tire is then cured by heat while under such pressure, after which the pins are withdrawn and the mold sections separated. 'The pins and mold parts are suitably treated to prevent the material from. adhering thereto as will be well understood by those skilled in the art. In case the cores are to be made of a material separate from or different than that of the tire body, the inner end of each pin is first filled with such core substance, which becomes firmly united to the tire substance during the compressing and curing operation.

The shape, size, depth, and arrangement of these recesses and cores is entirely within the selection of the tire maker. As a satisfactory example. but without intent to limit myself thereto, I will instance the following dimensions: exterior diameter of tire-34 inches; thickness of tire4c inches; width at base-4) inches width at tread-3 inches; diameter of hole inch; depth of l1ole- The re 15, each of which is 3;} inches; diameter of core-{ inch; incl1nat1on of hole12 from radius.

It will be understood that I do not confine myself to this particular type of tire or to this particular process of manufacture or to any of the dimensions, details, designs, or arrangements herein set forth except as the same are specifically recited in my claims.

Having thus described my invention, What I claim is: 1

1; Apparatus for tire manufacture com-. prising, in combination, a ring adapted to surround the tire tread and having a plurality of apertures therein, a plurality of cellular pins adapted to be inserted through said apertures into the body of the tire material, and mold members adapted to overlap said ring and the inner portion of the tire and to engage the sides thereof.

2. Apparatus for tire manufacture comprising, in combination, a pair of interfitting rings adapted to surround the tire tread and each'having a plurality of apertures therein, a. plurality of cylindrical pins adapted to be inserted through said apertures into the body of the tire, mold members adapted to engage said rings and the sides'of the tire, and a retaining ring adapted to surround said pins.

3. Apparatus for tire manufacture comprisin in combination, a'ring adapted to surround the tire tread and having therein a. plurality of apertures regularly arranged, a plurality of cylindrical pins adapted. to be inserted through said apertures into the body of the tire, each of said pins having its inner end hollow, and having a vent extending outwardly from the base of such hollow portion, and a pair of mold members adapted to engage said-ring and the side of the tire, said ring and mold members having telescoping inter-engagement whereby pressure can be exerted upon the tire composition.

4. Apparatus for tire manufacture comprising, in combination, a pair of inter-fitting rings adapted to surround the tire tread and having therein a plurality of apertures. a plurality of cylindrical pins adapted to be inserted, through said apertures into the body of the tire. each of said pins having its inner end hollow, mold members adapted to engage the parts of the tire other than the tread. and a'retaining ring adapted to surround said pins.

Apparatus for tire n'lanufacture comprising, in combination, a pair of mold mem bers having mating grooves in their adjacent faces. inner and outer rings adapted to project into said grooves and defining thcreabout a cavity the shape of a tire. the outer ring having therein a plurality of apertures which communicate with such cavity, pins adapted to be inserted into the said apertures and to project into such cavity, the heads of such pins occupying the space between the adjacent faces of the mold members, and means for retaining said pins against accidental displacement.

6. The process of making tires which includes the steps of enclosing tire material in an annular space, sticking hollow pins into such space, eneirtingf pressure laterally upon the meters in force ehe szune into the hollows n? the pins, curing zhe tires by heat While subjected its such ssure, emeving such pressure, and i'ememng the pins.

in testimony Whereofll hereunto afi'ix my signature.

:ennn ii. sonni'lnn. 

